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We present a versatile method for the preparation of mesoporous tin-doped indium oxide (ITO) thin films via dip-coating. Two poly(isobutylene)-b- poly(ethyleneoxide) (PIB-PEO) copolymers of significantly different molecular weight (denoted as PIB-PEO 3000 and PIB-PEO 20000) are used as templates and are compared with non-templated films to clarify the effect of the template size on the crystallization and, thus, on the electrochemical properties of mesoporous ITO films. Transparent, mesoporous, conductive coatings are obtained after annealing at 500 °C; these coatings have a specific resistance of 0.5 cm at a thickness of about 100 nm. Electrical conductivity is improved by one order of magnitude by annealing under a reducing atmosphere. The two types of PIB-PEO block copolymers create mesopores with in-plane diameters of 20-25 and 35-45 nm, the latter also possessing correspondingly thicker pore walls. Impedance measurements reveal that the conductivity is significantly higher for films prepared with the template generating larger mesopores. Because of the same size of the primary nanoparticles, the enhanced conductivity is attributed to a higher conduction path cross section. Prussian blue was deposited electrochemically within the films, thus confirming the accessibility of their pores and their functionality as electrode material.

Self-channeling properties of high intensity laser pulses are used to extend spectroscopic methods as LIBS to standoff. This work shows the advantages of using selfchanneled femtosecond pulses in Laser-Induced Breakdown Spectroscopy of polymeric micrometer-size thin films in a standoff configuration at 12 meters. We show the possibility of trace analysis on surfaces and the importance of molecular signal as a signature for carbon-based samples., Presented at the IEEE International Conference on Technologies for Homeland Security (HST-09) held in Waltham, Massachusetts on 11-12 May 2009. Publsihed in the Proceedings of the IEEE International Conference on Technologies for Homeland Security (HST-09), p472-476, 2009.

The goal of this research is to investigate theoretically and experimentally the feasibility of a new Multi-State Spectral Sensing (MS3) concept where bio-signature information can be collected from multiple metastable conformations for enhanced sensing in the THz region. Several geometric isomeric molecular systems have been investigated including 2-butenes, retinals, and stilbenes, in order to (1) study THz spectra of different molecular conformation; (2) illustrate a basic procedure through which optical excitation can be used to modify molecular conformations; (3) study possible binding of stilbene or its derivatives to DNA terminal. We have conducted the initial theoretical investigation of emission of radiation by DNA., Prepared in collaboration with U.S. Army, ECBC. The original document contains color images.

Lithium cation catalyzed radical copolymerization of isobutylene with ethyl acrylate has been examined. Up to 30% of isobutylene is incorporated at 1 atm pressure, and molecular weights up to a million have been observed., The original document contains color images.

This research determined the rate and extent of aerobic degradation of fuel oxygenates ethyl tert butyl ether (ETBE), tert amyl methyl ether (TAME) and ethyl alcohol (ethanol). Biodegradation was measured using gas chromatography (GC), respirometry, and biochemical oxygen demand (BOD) tests. Additionally, the research determined the effects of toluene on degradation rates. This microcosm study used a microbial consortium obtained from a petroleum refinery wastewater treatment facility. Respirometry data were collected from chambers containing pure oxygenates, or oxygenate/toluene mixtures. Samples were withdrawn periodically for GC analysis. Aerobic conditions were maintained in the chambers at all times. Degradation of oxygenates was compared to degradation of toluene, assuming first order decay. Across all experiments TAME degraded at 8.65 % the rate of toluene, ETBE at 8.17% the rate of toluene and ethanol at 156.79 % the rate of toluene. GC and respirometry data were the most suitable methods for measuring degradation. BOD provided acceptable results for toluene and ethanol but not for the slower degrading oxygenates. Finally, the presence of toluene slowed the degradation of both ETBE and TAME., The original document contains color images.

This program studies fundamental chemical kinetics as well as its individual and coupled effects with aerodynamics on laminar nonpremixed ignition and flame propagation for hydrocarbons, through experimental, computational, and theoretical approaches. During the reporting period, three projects were undertaken, namely: (1) Experimental determination of high-pressure laminar flame speeds and kinetic modeling of carbon-monoxide I hydrogen combustion; (2) experimental and computational determination of the ignition temperatures and reaction mechanism of 1,3-butadiene at atmospheric and elevated pressures; and (3) experimental and computational studies on the ignition of the butene isomers., Presented at the ARO/AFOSR Contractors' Meeting in Chemical Propulsion held in Arlington, Virginia on 12-14 Jun 2006. This article is from ADA474195 Army Research Office and Air Force Office of Scientific Research Contractors' Meeting in Chemical Propulsion Held in Arlington, Virginia on June 12-14, 2006